1. Technical Field of the Invention
This invention relates to cellular telecommunication systems and, more particularly, to a method of transferring data to and from a mobile station in a cellular telecommunications network.
2. Description of Related Art
In existing cellular telecommunications networks, each mobile station (MS) is registered with the cellular network through a single base station (BS). In doing so, the MS uses a radio link comprising one Voice Channel (VC) for the transfer of voice and data, and one Control Channel (CC) for the transfer of control signals. Thus, in existing networks, the data transfer rate is limited by the bandwidth of the radio link.
One of the most difficult limitations to overcome in existing cellular systems is the bandwidth limitation of the radio link. The radio link bandwidth generally limits data transfer rates, even when utilizing multi-slot transmission, to approximately 28.8 kbps. Proposed third generation (3G) systems may increase this rate to a range of approximately 100 kbps to 400 kbps. Over short distances, 3G systems may achieve transfer rates as high as 2 Mbps, but this is still much slower than the transfer rate of 100 Mbps which is achievable over a fixed wireline. The higher wireline transfer rate allows users on the Public Switched Telephone Network (PSTN) to enjoy applications such as multimedia and video on demand, whereas cellular subscribers currently have fairly limited access to such applications.
Although there are no known prior art teachings of a solution to the aforementioned deficiency and shortcoming such as that disclosed herein, U.S. Pat. No. 4,914,651 to Lusignan discusses subject matter that bears some relation to matters discussed herein. Lusignan discloses a system for increasing the data transfer rate in an Advanced Mobile Phone System (AMPS) cellular network. In Lusignan, an extra data channel is defined for each voice channel in a cell. The extra data channels are assigned a frequency of 15 KHz higher or lower than the center frequency of the associated voice channel. This frequency assignment minimizes interference with the associated channel frequency and adjacent cells which follow the cellular network frequency reuse plan. However, Lusignan is limited to utilizing whatever channels are available in a single BS, and dramatically increases the load on that BS.
Review of each of the foregoing references reveals no disclosure or suggestion of a system or method such as that described and claimed herein.
In order to overcome the disadvantage of existing solutions, it would be advantageous to have a method of transferring data to and from a mobile station in a cellular telecommunications network which is not limited to available channels in a single BS. Such a method would enable a MS to simultaneously seize additional voice channels or control channels from adjacent cells in order to increase the data transfer rate.
The present invention is a system and method of transferring data to and from a MS in a cellular telecommunications network. When a data transmission is desired, the MS simultaneously seizes additional voice channels or control channels from adjacent cells and asynchronously transmits packets of data over the plurality of channels in order to increase the data transfer rate. Such a method makes video/multimedia applications possible in the cellular network because, in effect, the radio-link bandwidth increases as many times as there are connections to the MS. For example, a MS connected to three BSs will have roughly three times the bandwidth. If multiple-slot transmissions are utilized on each connection, the data transfer rate increases even more dramatically. In addition, by asynchronously transmitting data packets on a plurality of connections, dedicated connections for data transmissions are not required. This decreases the load on the network by making more efficient usage of network resources.